Panchang in Sevan, Gegharkunik, Armenia Tue 11 May 1915

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 23:57 on Mon 10 May to 01:56 on Wed 12 May, so only Tuesday’s pradosha (19:02–20:59) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Sevan

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 324°–336° is the 28th, Krishna Trayodashi. A day takes the tithi in force at its sunrise, 04:48 here. Dwadashi ended at 23:59 Mon, before it. Trayodashi ends at 01:58 Wed, when the lead reaches 336°. The lead passed 180° at the full moon of 29 Apr, so the Moon is waning: Krishna paksha.

The night of Mon 10 May ran from sunset 19:03 Mon to sunrise 04:48, 9 h 45 m. Cut into 15 muhurtas of 39 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 04:48 to 19:04, splits into 8 choghadiyas of 1 h 47 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 19:04 to 04:47 Wed, splits into 8 choghadiyas of 1 h 12 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The fixed stars divide the Moon's path into 27 nakshatras of 13°20′, each in 4 padas of 3°20′. Revati spans 346°40′–360°00′; the Moon entered its pada 2 at 350°. It leaves at 19:01, for Ashwini.

Add the Sun's and the Moon's places among the stars: 26.6° + 352.9° = 379.5°, one full turn and 19.5°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 13°20′–26°40′ is the 2nd, Priti. It ends at 18:02, then Ayushmana.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Trayodashi is Garaja and the second Vanija. Garaja runs until 12:56, when the lead reaches 330°; Vanija until 01:58 Wed.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 04:48 to 04:47 Wed, so the hours after midnight still belong to Mangalawara.

A month normally holds one sankranti, the Sun's entry into a new rashi. From 14 Apr 14:35 Wed to 14 May 06:30 Fri the Sun stayed in Mesha, entering Vrishabha at 14 May 16:42 Fri, after the new moon. A month with no sankranti is Adhika Vaishakha, before Vaishakha itself.

A purnimanta month runs from full moon to full moon, so its waning half comes first. It shares its name with the amanta month that its second half falls in: the new moon of 14 May, with the Sun in Mesha, begins Vaishakha (Adhik). Until then this Krishna paksha reads Vaishakha (Adhik) here, and Vaishakha (Adhik) in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 15 Mar 1915, 22:41 Mon. Since then the Sun has moved 55.1° round the stars. Vikram Samvat numbers that year 1972; Shaka Samvat numbers it 1837.